I want to simulate a flow through vent.
The flow velocity is very small. So Reynold No. is below 2300 and I should have a laminar flow.
The behavior of the fluid is similar to "Shear thinning" fluids.
In the first step I simulated a Newtonian flow. I applied SimpleFoam and all was really fine.
Now I am testing the CrossPower- law and
at the moment at my wits' end:

As soon as I set CrossPower- exponent n <> 0 then I get the following error:

I applied SimpleFoam in FoamX the GUI (graphic user interface) of OpenFoam.
There is a programming error. The program produces script code.
The dimension vectors in the script code for CrossPowerLaw and BirdCarreauLaw are without dimensions: